POE Power Supply Mode

POE power supply is achieved through the network cable, and the network cable is composed of four pairs of twisted pairs (8 core wires), so the eight core wires in the network cable are the PoE switch to provide data and power transmission media for the receiving device. At present, PoE switches provide transmission compatible DC power to the receiving End devices through three PoE power supply modes: Mode A (end-SPAN end crossover), mode B (Mid-Span middle crossover) and 4-pair.

• Mode A PoE power supply mode

Mode A is end-span. In this mode, the PoE switch supplies power to the receiving End device through 1, 2, 3, and 6 wires, and also transmits data. 1 and 2 are positive terminals, and 3 and 6 are negative terminals..

• Mode B PoE power supply mode

Mode B is the Mid-Span mode. In this mode, the PoE switch supplies power to the receiving device through 4, 5, 7, and 8 wires. When applied to 10BASE-T and 100BASE-T Ethernet, 4, 5, 7, 8 lines will only carry out power transmission, will not carry out data transmission, so the four feet are also called idle feet. Where 4, 5 as the positive electrode, 7, 8 as the negative electrode.

• The 4-pair PoE power supply mode

In this mode, the PoE switch will supply power to the receiving device through all lines, where 1, 2, 4, and 5 are positive terminals, and 3, 6, 7, and 8 are negative terminals.

It should be noted that the PoE power supply mode is determined by the power supply device, and the PoE switch and PoE power supply (power injector) can be used as the power supply device to carry out power and data transmission for the receiving device. As A power supply device, the PoE switch generally uses mode A for power supply. Generally, the PoE injector is used as an intermediate device to connect the non-standard PoE switch and the receiving device. It can only support the PoE power supply mode in mode B..

 PoE power supply distance: Because power and network signals are easily affected by resistance and capacitance when transmitted on the network cable, resulting in signal attenuation or unstable power supply, the transmission distance of the network cable is limited, and the maximum transmission distance can only reach 100 meters. PoE power supply is realized through the network cable, so its transmission distance is affected by the network cable, and the maximum transmission distance is 100 meters. However, if the PoE extender is used, the PoE power supply range can be extended to a maximum of 1219 meters.

PoE power supply mode is roughly introduced in the above content, as for the switch series products mentioned above, they are popular communication products in Shenzhen HDV Phoelectron Technology LTD., such as: Ethernet switch, Fibre Channel switch, Ethernet Fibre Channel switch, etc., the above switches can be used in a variety of scenarios, to provide more choices for users with different needs, welcome to come to understand, we will provide the best quality service.